Apparatus for making concrete blocks

ABSTRACT

A HIGH CAPACITY FOR CURING CONCETE BUILDING BLOCKS COMPRISING A KILN HAVING OPEN FRONT AND REAR ENDS AND HAVING A PLURALITY OF SUPPORT ELEMENTS THEREIN TO DEFINE A PLURALITY OF PASSAGES ARRANGED IN HORIZONTAL ROWS, ONE ABOVE THE OTHER. A VERTICALLY SHITABLE HORIZONTAL ROWS, ORIENTED INFEED CONVEYOR MECHANISM POSITIONED TRANSVERSELY OF AND CLOSELY ADJACENT THE FRONT END OF THE KILN FOR CONVEYING UNCURED BLOCKS TO THE KILN, AND A VERTICALLY SHIFTABLE HORIZONTALLY ORIENTED REMOVAL CONVEYOR MECHANISM POSITIONED TRANSVERSELY OF AND CLOSELY ADJACENT THE REAR END OF THE KILN FOR RECEIVING CURED BLOCKS FROM THE KILN. MEANS FOR SIMULTANEOUSLY SHIFTING THE CONVEYOR MECHANISMS VERTICALLY AND A BLOCK SHIFTING MECHANISM CARRIED BY THE INFEED CONVEYOR MECHANISM FOR SUCCESSIVELY FEEDING UNCURED BLOCKS, ONE AT A TIME INTO THE PASSAGES.

D. D. scHwELLENBAcl-l 3,671,165

June 20, 1972 Filed Aug. 28, 1969 D. D. scHwELLl-:NBACH 3,671,165

APPARATUS FOR MAKING CONCRETE BLOCKS 4 Sheecs--Sheefl 2 `Fume 20, 1972 Filed Aug. 28, 1969 I NVE NTOR. 00A/4u: D. ScHu/fLf/@Acf/ HB4 BY June 20, 1972 D. D. scHwELLl-:NBACH 3,671,165

APPARATUS FOR MAKING CONCRETE BLOCKS 4 Sheets-Sheet 5 Filed Aug. 28. 1969 INVENTOR 90A/4.4.0 D. Seau/afnam ge/0M A 7 mea/EVS June 20, 1972 D. D. scHwr-:LLENBACH 3,671,165

A'PPARATUS FOR MAKING CONCRETE BLOCKS Filed Aug. 28, 1969 4 Sheets-Sheet 4 ATTORNEYS United States Patent Omce 3,671,165 Patented June 20, 1972 3,671,165 APPARATUS FOR MAKING CONCRETE BLOCKS Donald D. Schwellenbach, 124 S. Filmore, Pierre, S. Dak. 57501 Continuation-impart of application Ser. No. 646,373, June 15, 1967. This application Aug. 28, 1969, Ser. No. 853,914 The portion of the term of the patent subsequent to Feb. 3, 1987, has been disclaimed Int. Cl. F27b 3/18 U.S. Cl. 425-445 4 Claims ABSTRACT OF THE DISCLOSURE A high capacity apparatus for curing concrete building blocks comprising a kiln having open front and rear ends and having a plurality of support elements therein to define a plurality of passages arranged in horizontal rows, one above the other. A vertically shiftable horizontally oriented infeed conveyor mechanism positioned transversely of and closely adjacent the front end of the kiln for conveying uncured blocks to the kiln, and a vertically shiftable horizontally oriented removal conveyor mechanism positioned transversely of and closely adjacent the rear end of the kiln for receiving cured blocks from the kiln. Means for simultaneously shifting the conveyor mechanisms vertically and a block shifting mechanism carried by the infeed conveyor mechanism for successively feeding uncured blocks, one at a time into the passages.

This is a continuation-in-part application of my copending application, Ser. No. 646,373, tiled June l5, 1967, now Pat. NO. 3,492,704.

SUMMARY OF THE INVENTION An object of this invention is to provide a high capacity apparatus system, of simple and inexpensive construction and operation, for curing concrete building blocks, including means for conveying uncured concrete blocks from a block making machine to a curing kiln where the blocks are urged into and through the kiln with provision for continuous removal of the blocks from the kiln, whereby the apparatus system is especially adapted for a continuous line operation.

A more specific object of this invention is to provide a novel high capacity apparatus for curing concrete building blocks including a kiln and adjustable infeed and removal conveyors for conveying uncured blocks to and removing cured blocks from the kiln, and block shifting means for urging the blocks from the infeed conveyor into and through the kiln so that cured blocks are successively urged upon the removal conveyor for transfer to a convenient stock pile or the like.

These and other objects and advantages of this invention will more fully appear from the following description made in connection with the accompanying drawing wherein like reference characters refer to the same or similar parts throughout the several views, and in which:

BRIEF DESCRIPTION OF THE FIGURES OF THE DRAWING FIG. 1 is a perspective View of the novel concrete block curing apparatus;

FIG. 2 is a plan view of a portion of the apparatus taken approximately along line 2-2 of FIG. l and illustrating the means for vertically shifting the conveyor mechanism;

FIG. 3 is a cross-sectional view on an enlarged scale taken approximately along line 3--3 of FIG. 2 and looking in the direction of the arrows;

FIG. 4 is a cross-sectional view taken approximately along line 4-4 of FIG. 1 and looking in the direction of the arrows;

FIG. 5 is a perspective view of an enlarged scale of the block shifting means;

FIG. 6 is a perspective view diagrammatically illustrating certain parts of the block shifting means illustrated in FIG. 5;

FIG. 7 is a diagrammatic perspective View of the apparatus illustrating the pattern the uncured blocks are fed into the kiln;

FIG. 8 is a cross-sectional view of the block shifting means illustrating the position indexing mechanism;

FIG. 9 is a fragmentary perspective view of one embodiment of the guide means for use in guiding the support plates P through the kiln;

FIG. 10 is a modified form of the guide means illustrated in FIG. 9;

FIG. l1 is a side elevational view of the speed control means of the block shifting means;

FIG. l2 is a diagrammatic front elevational view of the kiln illustrating the sequence and pattern in which the blocks are fed into the kiln; and

FIG. 13 is an elevational view of the carriage used in removal of blocks from the kiln.

DETAILED DESCRIPTION OF THE INVENTION Referring now to the drawings, and more specifically to FIG. l, it will be seen that one embodiment of a high capacity apparatus for making concrete blocks and designated generally by the reference numeral 10 is thereshown. This apparatus includes a block making machine 11 of conventional construction and operation, which is operable to mold concrete blocks B in a well-known manner. It will be noted that the concrete blocks B, which are molded in the block making machine 11, -will be positioned upon a plate P, preferably formed of a suited rigid metallic material, such as steel or the like. The uncured blocks B are transferred from the block making machine 11 to a curing kiln 13 by an infeed conveyor mechanism 12. The curing kiln 13, as best seen in FIGS. l and 4, is of generally rectangular configuration and includes a top wall 14 and opposed side walls 15, and is provided with a oor or bottom Wall. The curing kiln has an open front end 16 and an open rear end 17, which intercommunicates the interior of the kiln with the exterior The kiln is provided with a plurality of vertically extending substantially parallel spaced apart front support posts 18, and a corresponding number of rear posts 19, which extend between the floor of the kiln and the top wall 14. Each front post 18 is disposed in longitudinal alignment with one of the rear posts 19 and each front and rear aligned pair of posts has a plurality of elongate rigid support elements or tracks 20 aixed thereto and extending therebetween. It will be noted that the tracks 20, which are rigidly secured to each post, are vertically spaced apart and are horizontally oriented, and in the embodiment shown are of angle cross-sectional construction. Each track is disposed in horizontal alignment with the adjacent track on the adjacent post, so that a plurality of passages 21 are delined, which extend completely through the kiln from the front end to the rear end thereof. It will be noted that these passages are arranged in horizontal rows or layers and these rows are arranged in vertical relation with respect to each other and are disposed in vertically aligned tiers. Each passage is adapted to support the support plates P upon which the uncured concrete blocks are positioned. The passages are therefore arranged in a grid pattern.

In this regard, it wil `be noted that each support plate P s adapted to support a pair of concrete blocks, although support plates for accommodating single concrete blocks or a plurality of blocks may also be provided. lt will also be noted that each support plate P has width and length dimensions which are slightly greater than the length and width dimensions of the pair of concrete blocks positioned thereupon, so that the marginal edge portions of the support plate project beyond the vertical edges of the uncured concrete blocks seated thereupon.

The infeed conveyor mechanism 12 comprises a sectional conveyor which includes a rst frame section 23 and a second frame section 24, which are pivotally connected together. The rst frame section 23 includes a pair of side walls 25, which are laterally spaced apart and rigidly interconnected by suitable transverse brace members 26. The second frame section 24 also includes a pair of side walls 27, which are rigidly interconected by transverse brace members 28. It will be noted, that the side walls 25 of the rst frame section 23 are pivotally connected at one of their respective ends 'by a pivot 29 to the side walls 27 of the second frame section.

The second frame section 24 is vertically shiftable on a conveyor support structure 31 for vertical shifting movement relative to the open front end of the kiln 13. To this end, it will be noted that each of the side walls 27 has vertical sleeves 30 affixed to opposite ends thereof and these sleeves are positioned on substantially tubular vertically oriented guide rods 32 of the conveyor support structure 31. The upper and lower ends of adjacent guide rods 32 are rigidly interconected by upper and lower transverse end frame members 33, as best seen in FIG. l. It will be noted that the upper end frame members 33 are rigidly interconected by longitudinal frame members 34, the purpose of which will be more fully described hereinbelow.

A pair of elongate endless conveyor chains 35 are trained about sprockets 36, which are mounted on shafts 37, but ar journalled in the side walls of the rst and second frame sections 23 and 24, respectively. The upper runs of the chains 35 support the plates P and convey the same into position for introduction into the kiln 13. It is pointed out that drive means are provided for driving one pair of the sprockets 36 and this drive means comprises an electrical motor, having suitable drive connections with the driven sprockets. Although not shown in the drawing, the first frame section 23 and that portion of the endless conveyor chains 35 supported thereon will be positioned closely adjacent the outlet of the block making machine 11, to receive concrete blocks therefrom and to convey the blocks into position for introduction into the kiln 13. The second frame section 24 is positioned in close proximity to the open front end of the kiln 13 and extends transversely of the kiln throughout the width thereof. This second frame section 24 is horizontally oriented, even though it is vertically shiftable relative to the kiln.

Referring now to FIGS. l, 2 and 3, it will be seen that means are provided for vertically shifting the infeed conveyor mechanism 12, and this means comprises a piston and cylinder unit including a hydraulic cylinder 39 having a piston axially movable therein to which is connected a piston rod 40, which extends axially outwardly from the cylinder 39. One end of the cylinder 39 is connected by a bracket 41 to a cross brace 42, which extends between and is rigidly affixed to the longitudinal frame members 34 of the conveyor support structure 31.

The front end of the cylinder 39 is also secured to a cross brace 43 by a bracket 44 and a pair of elongate spaced apart substantially parallel channel-shaped track members 45 extend between and are rigidly secured to the cross brace 43 and one of the end transverse members 33. lt will be noted that the track members 45 are positioned interiorly of and spaced from the longitudinal frame members 34. The free end of the piston rod 40 has a cross member 46 secured thereto and slide blocks 47 are secured to the cross member 46 and are positioned in the track members 45. A plurality of cables 48 each have one end secured to the cross member 46 and these cables are thereafter trained about pulleys 49, which are revolvably mounted on the cross brace 42. These cables are thereafter trained about vertically oriented pulleys 50 located at opposite ends of the transverse frame members 34 and the ends of these cables 48 are secured to suitable apertured brackets 51 carried by the Sleeves 30. Extension and retraction of the piston rod 40 causes the cables 48 to be progressively tensioned or relaxation of the tension to thereby cause raising and lowering of the infeed conveyor mechanism 12. It will also be noted that the cross member 46 has a pair of cables 52 connected thereto, and these cables are trained over a pair of pulleys 53 mounted on a support plate or bracket 54, secured to one of the end frame members 34. These cables are then extended rearwardly and are connected `with a removal conveyor mechanism for shifting this conveyor mechanism vertically simultaneously with shifting movement of the infeed conveyor mechanism.

This removal conveyor mechanism 55 is similar in construction to that part of the sectional infeed conveyor mechanism that is carried by the second frame section 24. The removal conveyor mechanism includes a conveyor support frame 56 comprised of a pair of side walls 57 connected by suitable cross braces 58k. The side walls have suitable sprockets thereon about which are trained a pair of driven endless conveyor chains 59. A conveyor support structure 60 is also provided and is identical in construction to the conveyor support structure 31 and includes a plurality of vertical guide rods 61 interconnected at their upper and lower ends by transverse end frame members 62, the upper end frame members being rigidly interconnected by suitable longitudinal frame members (not shown). The side walls 57 have sleeves at opposite ends thereof, -which are positioned around and are slidable upon the guide rods 61 in the manner of the infeed conveyor mechanism 12.

The cables 52, which extend rearwardly from the front conveyor support structure 31 are trained about pulleys 63 mounted on the end frame member 62 and extend downwardly therefrom and are connected to cable type slings 64, which are secured to opposite ends of the side walls 57. Thus, it will be seen that when the infeed conveyor mechanism 12 is raised or lowered, the removal conveyor mechanism 55 will be simultaneously raised and lowered. Therefore, the infeed and removal conveyor mechanisms are maintained at the same level as each other.

Means are provided for releasa-bly locking the infeed and removal conveyor mechanisms in an adjusted vertical position. Referring again to FIGS. 2 and 3, it will be seen that this locking means includes a pair of elongate serrated locking members 65, each having a plurality of notches 66 therein and each being rigidly secured to the upper surface of one of the track members 45. The cross member 46 has a pair of arms 66 rigidly secured thereto and projecting upwardly therefrom adjacent opposite ends of the cross member. It will be noted that the arms 66 are of generally angle shaped configuration and a rock shaft 67 extends between these arms and is journalled thereon. The rock shaft 67 has a pair of elongate latch element arms 68 secured thereto for movement therewith.

Means are provided for shifting the latch elements 68 into and out of engaging relation with the locking member and this means includes a solenoid actuator 69 mounted on one of the arms 66 and having its plunger 70 secured to the associated latch element 68. Electrical conductors 71 interconnect the solenoid to a source of electrical current and a suitable manually or automatically operable control switch (not shown) is interposed in the circuit whereby an operator may very easily shift the latch elements into or ont of engaging relation with respect to the locking members.

Means are also provided for pushing or urging the blocks from the infeed conveyor mechanism successively into one of the kiln passages 21 and this block shifting means, designated generally by the reference numeral 72 comprises a kgenerally rectangular shaped support or frame structure 73, which includes longitudinal frame members 74 interconnected by vertical frame members 75 and transverse frame members 76, as best seen in FIGS. 1, and 6. Rollers 77 are provided on the vertical frame members 75 and engage the upper surface of the side walls 27 of the second frame section 24. It will be noted that this second frame section 24 projects through the frame structure 73 interiorly of the vertical frame members and between the upper and lower transverse frame members. The rollers 77 permit the frame` structure 73 to be moved longitudinally of the second frame section 24.

The block shifting means 72 also includes a relatively large hydraulic piston and cylinder unit comprised of a cylinder 78, having a piston movable therein to which is connected a piston rod 79, which projects axially from the cylinder. The outer end of the piston rod has a pressure plate 80 secured thereto, and it will Ibe noted that this pressure plate is vertically oriented. Elongate mounting straps 81 are secured to the rear end of the cylinder 78 and are secured to the frame structure 73 to rigidly support the cylinder on the frame structure. Brackets 82 are secured to the forward end of the cylinder 78 and are mounted on a longitudinal frame member 74, so that the cylinder is supported rigidly in a horizontal position. Extension of the piston rod 79 from a retracted position will extend the piston rod transversely of the frame structure 73.

Means are provided for elevating each plate P that has concrete blocks thereon from supported relation on the endless conveyor chains 35 into position for entry into one of the passages 21 of the kiln 13. This block elevating or lifting means comprises a generally rectangular shaped frame 83, which is positioned interiorly of the frame structure 73. This rectangular frame 73 is dimensioned to pass between the endless conveyor chains 35 and has a pair of upstanding spaced apart guide rods 84, rigidly affixed thereto and projecting upwardly therefrom adjacent one side thereof. Suitable pillow bearings 85 are mounted on the frame structure 73, adjacent one end thereof. In the embodiment shown, these pillow bearings 85 are mounted on the frame structure 73 on the most distal exterior end portion of the frame structure 73, as viewed in FIG. 5.

A hydraulic piston and cylinder unit is provided for vertically shifting the rectangular frame 83 and this unit includes a cylinder 85 which is secured by a bracket 85a to the frame structure 73. The cylinder 86 has a piston movable therein and a piston rod 87 is secured to the piston and projects exteriorly of the cylinder and is secured to a relatively rigid rod 88, which extends between and is connected with the guide rods 84. It will therefore be seen that when the piston and cylinder unit is extended and retracted, the frame 83 will be raised and lowered. Although not shown in the drawing, a suitable limit switch or its equivalent will be used to limit elevation of frame to properly align the plate P with respect to the tracks 220 and 220a described hereinbelow.

A lever 89 is pivotally mounted intermediate its ends upon the frame structure J73 adjacent one corner thereof by a pivot 90, as best seen in PlIGS. 5 and 6. This lever has one end pivotally connected to one of the guide rods 84 by a pivot 91 and has its other end pivotally connected by a pivot 92 to the operator arm 93 of a valve mechanism 94. This valve mechanism 94 is disposed in ow controlling relation with respect to a pair of conduits 95, which are connected to a double acting cylinder 78 and which are also connected to a source of hydraulic liquid under pressure. Therefore, when the rectangular frame |83 is elevated, the valve mechanism 94 will be actuated to extend the piston rod 79. A micro-switch 96 having a switch actuating element 97 is mounted on the frame structure 73 adjacent one end thereof, as best seen in FIG. 5, so that when a plate P strikes the switch actuator element the micro-switch will be closed, which in turn controls a solenoid valve (not shown) that operates the piston and cylinder unit to thereby extend the piston rod 87. When the micro-switch element is opened, the piston rod 87 will be retracted.

Means are provided for releasably locking the frame structure 73 to the kiln and this means comprises a pair of hooks or locking elements 98, each being secured to one of a pair of shafts 99, which in turn are journalled in sleeves 100 that are secured to the frame structure 73. It will be noted that the hooks 98 project from the frame structure 73 when the hooks are in the extended locking position for engagement with a pair of posts 18. Suitable keeper straps are provided for retaining the hooks 98 in horizontal relation, and it is pointed out that these hooks are swingable between an extended position, as illustrated in FIG. 5, to a retracted position, wherein the hooks rotate with their associated shaft from the extended position towards each other.

The means for moving the hooks between locked and unlocked positions comprises a hydraulic piston and cylinder unit including a cylinder 102, which is mounted on the frame structure 73 by a bracket 103, and which has a piston movable therein to which is secured a piston rod 104. The free end of the piston rod 104 is Ipivotally connected to a pair of links 105, as -best seen in FIG. 5. Each of these links 105 is pivotally connected to a crank arm 106, each crank arm being pivotally amounted on the frame structure 73 by a pivot 107. It will therefore be seen that when the piston and cylinder unit is extended and retracted, the hooks 98 will be shifted between opened and closed positions. All of the hydraulic piston and cylinder units will be connected to a suitable source of hydraulic fluid under pressure and it is pointed out that operation of the hydraulic and piston unit for controlling the hooks 98 will be manually controlled in the embodiment shown.

Means are also provided for indexing the block shifting means 72 so that the frame structure 73 is positioned in alignment with one of the kiln passages 21. This indexing means, as best seen in FIG. 8, includes a plurality of similar indexing blocks 130, which are affixed to one of the side walls 27 of the second frame section 24. Each of these indexing blocks has an upper surface 131 which is provided with a notch 132 therein. -Each block also has a raised cam 133 projecting upwardly from the upper surface thereof. It will Ibe noted that each cam 133 is located at the leading end of each indexing block 130.

A bracket 134 is aixed to one of the vertical frame members 135 of the frame structure 73. A bracket 134 has an arm 135 pivotally connected thereto by means of a pivot 136. It will be noted that the arm 135 has an angulated extension 137 integrally formed therewith and projecting therefrom. The arm 135 is vertically swingable about a substantially horizontal axis defined by the pivot 136.`

A sprocket 13 is journalled on one end of the arm 135 and the sprocket is provided with a slip clutch 139. A fluid pressure cylinder 140 is also pivotally connected at one end to one of the vertical members 75 of the frame structure 73 and is provided with a piston which is axially shiftable therein. A piston rod 141 is secured to the piston for movement therewith and projects exteriorally of the cylinder 140 and is pivotally connected to the arm 135. The fluid pressure cylinder 140 is connected to a source of hydraulic pressure so that extension and retraction of the piston rod causes the arm 13S to swing about its pivotal axis. It will be seen that when the piston rod 141 is retracted, the arm 135 will be pivoted so that the angulated extension 137 will engage in the notch 132 of an index block 130. When this occurs,

the frame structure 73 will be locked against movement with respect to the curing kiln.

A switch 142 is also secured to a vertical frame member 75 of the frame structure 73 and the switch is provided with a switch arm 143. It will be seen that the switch arm 143 is disposed in obstructing relation with respect to the raised cam 133 on each index in block 130. Therefore, if the frame structure 73 is moved relative to the second frame section 24, then the switch arm 143 will eventually engage one of the raised cams 133. When this occurs, the switch will energize a solenoid valve thus causing retraction of the piston rod 141 and releasable engagement of the arm with one of the index block notches 132. This releasably locks the frame in position so that the block may be discharged in one of the kiln passages. In order to disengage the extension 137 from the notch 132 of an index 130, a separate control valve is operated which extends the piston rod 141 and moves the extension 137 out of engagement with the notch 132. When this occurs, the sprocket 138 is urged into engaging relation with the conveyor chain 35, whereby causing the block shifting means '72 to be urged transversely of the curing kiln. The slip cl-utch 139 permits the sprocket to slip thereby minimizing damage when the sprocket initially engages the conveyor chain.

Means are also provided for controlling the rate in which the blocks are introduced into the kiln. To this end, an elongate cam bar 150 is secured to the pressure plate 80 that is afxed to the outer end of piston rod 79 as best seen in FIG. 1l. The upper surface of the cam bar 150 constitutes a cam which includes a first raised cam surface 151. A second cam surface 152 is of convex configuration and is spaced from the first cam surface 151. A third cam surface 153 is spaced from the second cam surface 152. It will be noted that the linear surface between the respective raised cam surfaces is substantially level and horizontally oriented.

A valve 145 having a valve actuator arm 146 is positioned above the cam 150. The valve is secured to a suitable support member carried by the frame structure 73. The valve actuator ar-m 146 has a cam follower or roller 14f7 journalled on the outer end thereof which engages the carn bar 150. lIt will be seen that as the piston rod 79 is extended, the cam follower will move along the upper surface of the cam bar and Vwill move progressively downwardly along the first raised cam surface 151 and then along the level horizontal surface of the cam bar. Then the follower will be cammed upwardly by the second raised cam surface and thereafter along the intermediate level surface between the second and third raised cam surfaces. Finally, the cam follower will be moved upwardly by the third cam surface.

It is pointed out that the valve 145= is interposed in flow controlling relation with respect to conduit 95 as best seen in FIG. 6i. With this arrangement, when the valve actuator 146 is urged upwardly, the ow of hydraulic fluid to the cylinder 78 will be diminished so that the piston rod is extended at a relatively slow rate. Thus, during the initial portion of the extension stroke of the piston rod 79, the piston rod will be moving fairly slowly so that as the pressure plate 80 is moved into engagement with the plate P upon which the uncured blocks are supported, there will be little likelihood of damage to the uncured blocks. Thereafter, the piston rod 79 is extended at a faster rate of speed until the follower is raised by the second cam surface 152. At this time, the plate and block supported thereon will be positioned for entry into the kiln passage 21. Thus, movement of the plate and block thereon is slow as the plate approaches entry into the passage 21. Thereafter, the piston rod 79 is returned to its normal speed so that the plate and block thereon is urged into the passage and at the terminal portion of the stroke, the rate of movement of the piston rod is progressively reduced by the third raised cam surface 153.

Means are also provided for synchronizing movement of the block shifting means 72 and the carriage 108 transversely of the kiln. To this end, it will be seen that an elongate cable 154 has opposite ends thereof secured to the block shifting means 72 and the carriage 108 respectively. The cable 154 is trained about a pulley 155 which is secured to a transverse frame element extending between a pair of sleeves 30 of the conveyor section 24. The cable extends downwardly and is then trained about a pulley 158 which is affixed to a support surface between a pair of front posts 32.

The cable 154 is then extended horizontally in a rearward direction and is trained about a pulley 163 located adjacent a rear corner of the curing -kiln and then extends upwardly and is trained about a pulley 164, the latter being secured to the kiln adjacent an upper rear corner thereof. The cable is then trained about a pair of pulleys 165 which are secured to a transverse frame element extending between a pair of the rear post 61. The cable extends downwardly and is then trained about a pulley 166 which is secured to the conveyor support frame 56 of the removal conveyor mechanism 55. It will therefore be seen that as the block shifting means 72 is shifted transversely in a direction to the left as viewed in FIG. 1, or FIG. l2, the carriage 108 will be simultaneously moved. It is pointed out that the block shifting means after having moved in a transverse direction to the last passage of a vertical row will then be returned manually by an operator to the vertical row of passages located to the extreme right as viewed in lFlG. 12.

Referring now to FIG. 9, it will be seen that means are provided for maintaining the plates P in horizontal abutting relationship with respect to each other. To this end, it `will be noted that tracks 220 identical to those shown in the embodiments of FIGS. 1 and 4 are secured to the front post 218 and to the rear post (not shown). Each track 220 is of angle construction and includes a vertical leg 221 which is secured to the posts in the manner of the tracks of FIG. 1. It will further be noted that each track 220 has its front end iiaired downwardly as at 222 and that the vertical leg thereof has its front end haired outwardly.

A generally angle shaped elongate guide member 224 including a vertical element 225 is rigidly aflixed to the vertical leg 221 of each track 220. Thus the space defined between each track 220 and each guide member 224 defines a guide which is of a size to receive plate P" but which prevents the plate P from tipping or being displaced upwardly so that the plates are maintained in abutting relation with respect to each other. This arrangement minimizes the occurrence of damage to the blocks as they are urged through the kiln.

Referring now to FIG. 10, it will be seen that a slightly different embodiment of the guide is thereshown. Tracks 220a of generally angle configuration are also provided and arranged in a manner of the tracks in FIG. 1. Tracks 220a include a vertical leg or element 221a which is secured to a front post 218a and to the rear post (not shown). The track 220a has a downwardly flaired front end and the vertical leg thereof also is flaired outwardly in the manner of the embodiment of FIG. 9. A guide member 224e: is secured to the track and includes a lower horizontal element 225a which is positioned upon the upper surface of the track 220a. The guide member 224a also includes a vertical element 226a which engages the vertical leg or element 221a and is rigidly secured thereto. An upper horizontal guide element 227:1 is integral with the vertical element 226:1 and is disposed in substantially parallel relation to the lower horizontal element 225a. The lower horizontal element terminates in a lower terminal end portion 228a which engages and is secured to the lower surface of the track 220a.

With this arrangement, the guide members guide the plates during movement of the plate and blocks thereon through the kiln. However, in the embodiment illustrated in FIG. 10, the lower horizontal element 225:1 serves as a wear surface with respect to the track 220e and these guide members may be removed as they become worn.

Referring now to FIG. 12, it will be seen that the pattern in which the blocks are introduced to the kiln is thereshown. The blocks are fed successively into the vertical tiers of the passages from right to left as viewed in FIG. 12. In other words, the first vertical tier of passages as viewed at the right of FIG. 12 will be filled and this may be done from top to bottom if desired. The block shifting means is then shifted to the next adjacent vertiral row of pasages. With this arrangement, the block shifting means 72 is moving in a lateral direction away from the supply of blocks as they are fed to the conveyor section 24. This permits a substantially continuous operation rather than feeding the blocks into the kiln in successive horizontal rows.

During operation of the device, blocks will be continuously made and discharged from the block making machine 11 upon the infeed conveyor mechanism 12. A pair of such blocks will be positioned upon each support plate P and each plate will be moved by the conveyor chains 35. The second frame section 24 will be positioned to discharge blocks into a selective kiln passage 21. To this end, the block shifting means 72 will be positioned or indexed in predetermined relation longitudinally of the second frame section 24 and the latter will be disposed in predetermined position with respect to the conveyor support structure 31.

The plate P with the pair of concrete blocks B mounted thereon will pass interiorly of the frame structure 73 until the blocks strike the micro-switch actuator element 97 of the micro-switch 96. This actuates a control solenoid valve to thereby extend the piston rod y87 and to elevate or raise the rectangular frame 83 from a lowered position. When the rectangular frame is in the lowered position, it will be positioned interiorly of the frame structure 73 but below the plate P, which is mounted on the conveyor chains 35. As the rectangular frame 83 is raised, it will engage and lift the plate P with the concrete blocks thereon from the conveyor chains 35 until the lever `89 operates the valve mechanism 94 to thereby extend the piston rod 79. The pressure plate 80 will engage the edges of the plate P and will push the plate with the blocks mounted thereon into one of the kiln passages 21.

As the concrete blocks are urged into the preselected passage 21, the plate P supporting the blocks will be moved out of engaging relation with respect to the microswitch actuator element 97. The piston rod 87 will be extended until the knob 121 on the rear end of a guide rod 120 on the piston rod 79 strikes the actuator element of a solenoid control valve (not shown) for retracting the piston rod 79.

It is pointed out that the guide rod 120 is slidable in a sleeve 122 which is mounted on brackets 82, the front end of the rod 120 being rigidly secured to the pressure plate 80.

When it is desirable to change the position of the block shifting means, a manual switch is operated to control the solenoid valve, that operates the piston and cylinder unit whereby the piston rod 104 is retracted. The hook 98 will be moved out of engaging relation with respect to a pair of the posts 18 and the block shifting means may then be indexed or shifted longitudinally of the second frame section 24 into a new desired position.

When it is desirable to change the position of the second frame section relative to the conveyor support structure 3.1, suitable switch means are operated, which control operation of a solenoid valve for the cylinder 39 and the piston rod 40' will be extended or retracted to properly position or index the second frame section at the desired elevation. During movement of the infeed conveyor mechanism, the removal conveyor mechanism 55 will be simultaneously moved or indexed. A separate switch and circuit will be provided for operating the solenoid actuator 69 so that the solenoid must be selectively energized or de-energized prior to raising or lowering the 10 infeed conveyor mechanism and the removal conveyor mechanism.

It is pointed out that blocks may be successively introduced into a selected passage until the passage is completely filled and thereafter when an additional block is urged into such a passage, a cured block will be forced outwardly of the opened rear end of the kiln. The removal conveyor mechanism 55 is provided with means for receiving each pair of cured blocks B on a support plate as they are ejected or urged outwardly of the kiln. To this end, a carriage 108 provided with rollers 109` is movable along longitudinally extending tracks 110, which are secured to the side walls 57 of the removal conveyor mechanism 55. The carriage 108 has a plurality of link arms 111 pivotally connected thereto and these link arms are also pivotally connected to a platform 112, which is swingable between collapsed and erect positions. The platform, carriage and link arms define a parallelogram linkage. It will be noted that when the platform is in the collapsed position, it is positioned upon the carriage and is spaced below the conveyor chains 59. However, when the platform is in the erect position, it is dimensioned to pass between the conveyor chains and at a high level relative thereto to receive the plate P with a pair of blocks thereon, whereby upon retraction, the plates with the cured blocks thereon will be positioned upon the conveyor chains.

The carriage 108` is provided with a bell crank lever 160 which is pivoted to carriage 108 by a pivot 161. The lever has a friction pad 159 secured thereto for engagement with one of the tracks 110. A spring 1'62 extends between the carriage 108 and lever 160 and urges the pad 159 into engaging relation with one of the tracks 110. However, when the cable 154 is tensioned, the cable pull will eventually overcome the action of the spring 162 and allow the carriage to move along the track 110'. Thus, precise positioning of the carriage 108 is maintained with this arrangement.

Means are provided for shifting the platform between erect and collapsed positions, and this means comprises a hydraulic piston and cylinder unit, including a cylinder 114 having a piston movable therein, which has a piston rod 115 connected thereto. The cylinder 114 is pivotally connected to the carriage, while the piston rod is pivotally connected to the platform. Thus, extension and retraction of the piston and cylinder unit shifts the platform between erect and collapsed positions. The piston and cylinder unit will be connected to a suitable source of hydraulic fluid under pressure, and it is pointed out that the platform 112 will be shifted to the erect position when the piston rod 79 is extended. With this arrangement, the platform will be raised when a plate P having blocks thereon is urged into one of the passages 21.

-Cured concrete blocks are discharged from the removal conveyor upon an apron conveyor 116, which is positioned adjacent one side of the kiln in the embodiment shown, and these cured blocks are moved and stock piled in a well-known manner. An apron-type return conveyor 117 is disposed in cooperating relation with the apron conveyor 116 receives the plate P therefrom to return the plates to the block making machine 11.

The interior of the kiln is heated by steam which is introduced by siutable apparatus Well known in the art. By utilizing only stationary support elements or tracks 20 within the kiln for supporting the blocks, maintenance problems with respect to the kiln are substantially reduced. Conventional curing kilns which use interior conveyor systems, such as chain conveyors, rollers and the like, that are exposed to steam, are constantly faced with maintenance problems. By using stationary tracks and an exteriorly located block shifting means, there are very few mechanisms that are subject to corrosion and damage by exposure to steam.

The kiln curing apparatus described hereinabove provides a means for high capaicty curing of uncured concrete blocks and obviates the necessity of the conventional equipment now associated with the transfer of the uncured blocks from the block making machine to the kiln. This conventional equipment includes fork Vehicles and the like, which requires considerably more labor than the present apparatus and also involve an interrupted type operation. The present process minimizes the use of man power, therefore affecting a substantial saving in labor.

It will therefore be seen from the foregoing description, that I have provided a novel curing apparatus for concrete blocks and the like, which is not only of simple and inexpensive construction and operation, but an apparatus which functions in a more eicient manner than any heretofore known comparable apparatus.

It will, of course, be understood that various changes may be made in the forni, details, arrangement and portions of the various parts without departing from the scope of my invention.

What is claimed is:

1. Apparatus for storing pallets of uncured concrete blocks during the curing thereof comprising a drying and curing kiln having a front infeed and a rear discharge end, a plurality of guideways in said kiln each of which extends from the front end to the rear end of said kiln, each of said guideways being proportioned to receive a yseries of the pallets being stored, said guideways being arranged in a pattern wherein guideways are disposed in horizontally aligned layers and vertically aligned tiers whereby the ends of said guideways adjacent said infeed and discharge ends are arranged in a rigid pattern, infeed conveyor means including means to feed pallets of blocks into any selected one of said guideways, discharge conveyor means adjacent the discharge end of said kiln, said discharge conveyor including means for receiving pallets of blocks from any selected one of said guideways, means interconnecting said means to feed said pallets and said means to receive said pallets so that both of said latter mentioned means are indexed vertically respectively at the level of the infeed and discharge ends of the guideways of a preselected layer and other means interconnecting said means to feed said pallets and said means to receive said pallets to that both of said latter mentioned means are indexed horizontally respectively to the infeed and discharge ends of the guideways of a preselected tier.

2. The apparatus as defined in claim 1 wherein said means to feed said pallets is shiftable longitudinally and vertically relative to Said infeed conveyor means.

3. The apparatus as defined in claim 1 wherein said means to receive pallets comprises a carriage shiftable longitudinally and vertically relative to said discharge conveyor means.

4. The apparatus as defined in claim 2 wherein said means to feed said pallets includes a fluid pressure motor unit including means extensible and retractable towards and away from said guideways.

References Cited UNITED STATES PATENTS 1,802,235 4/1931 Campbell 25--142 D 2,502,940 4/1950 Gelbman 25-133 3,172,527 3/1965 Swartz et al. 2114-164 X 3,245,129 4/1966 Entz 214-164 X 3,268,098 8/1966 Thomas et al. 214-16-.4 R 3,326,662 6/1967 Danielsson et al. 2l4-16.4 3,492,704 3/ 1970 Schnellenbach 25--2 X J. SPENCER OVERHOLSER, Primary Examiner B. D. TOBUR, Assistant Examiner U.S. Cl. X.R. 425-455 

